The review provides an overview of epidemiological studies that were carried out in the field of community noise and cardiovascular risk. The studies and their characteristics are listed in the tables. Risk estimates derived from the individual studies are given for 5 dB(A) categories of the average A-weighted sound pressure level during the day. The noise sources considered in the studies are road and aircraft noise. The health endpoints are mean blood pressure, hypertension and ischaemic heart disease, including myocardial infarction. Study subjects are children and adults. The evidence of an association between transportation noise and cardiovascular risk has increased since the previous review published in Noise and Health in the year 2000.

The goals of this study were twofold. First, we assessed if waking salivary hormone profiles are altered by nighttime noise exposure in a laboratory environment. Second, we evaluated the potential influence that sleeping in the lab in itself may have had on salivary biomarkers, by comparing results obtained following sleep at home. Twelve adults (7 males, 5 females) between 19-25 yrs slept at home and in a sleep laboratory. Subjects provided six saliva samples during waking hours on the day prior to sleep in the lab, on both days after sleeping in the lab and on the day following the resumption of sleep at home. Following one night of adaptation, subjects were exposed throughout the 2 ^nd night to simulated backup alarms that consisted of trains of 5 consecutive 500 ms duration audible tones. The time between the onset of each tone was 1 s and the time between trains (offset to onset) was 15 to 20 s. When compared to home conditions, cortisol and melatonin levels were higher following sleep in the laboratory 30 minutes after awakening. However, no significant differences were noted for any salivary biomarker between the 1 ^st and 2 ^nd night in the sleep lab, suggesting that these endpoints were not influenced by exposure to noise on the 2 ^nd night. Waking profiles of alpha-amylase were not influenced by where the subjects slept. Subjective reports of sleep disturbance following sleep in the lab were also obtained. For most of the day there was no apparent influence of the laboratory noise exposure. However, subjects did report more sleepiness during the evening (8 pm) following the 2 ^nd night in the laboratory. In general, overall sleep quality was rated slightly higher upon awakening from sleep at home. Factors that might have contributed to the observations in this study are discussed, including those related to the potentially non-representative sample.

In the present retrospective register study a very large data base consisting of screening audiograms obtained at military conscription of 18-year-old Swedish men was used. The study group comprised 450,175 men, aged 18 years, tested at conscription to military service. There were nine age groups covering a 24-year period, from 1971 to 1995. This database was compared with a number of different pre- and postnatal factors with possible influence on the hearing function. This ecologic methodology gives tentative clues (but no proof) of possible ototraumatic influences. The hearing capacity was fairly similar during the entire span of the study and only small variations were observed. There was a slight tendency of better hearing capacity in the later age groups, compared with the earlier ones. The mean thresholds of the frequencies 4 and 6 kHz were slightly elevated in 1971, 1976 and, to some extent also in1992. We tried to calculate the levels of leisure noise exposure during the study period. There was no apparent tendency of reduced noise levels, on the contrary the noise levels seemed to increase. The treatment programmes for acute otitis media (AOM) underwent considerable changes during the period from the early fifties to the early eighties, when the participants were pre-school children. One possible explanation for the slight improvement of the hearing capacity could be less ototraumatic influence of AOM. Data about the occurrence of four common epidemic diseases, covering the periods preceding and succeeding the years when the participants were born indicated that influenza and possibly pertussis (whooping cough), constitute putative prenatal risk factors for mild to moderate high frequency hearing loss.

Audiological testing, interviews and exposure measurements were used to collect data on the health effects of styrene exposures in 313 workers from fiberglass and metal-product manufacturing plants and a mail terminal. The audiological test battery included pure-tone audiometry, distortion product otoacoustic emissions (DPOAE), psychoacoustic modulation transfer function, interrupted speech, speech recognition in noise and cortical response audiometry (CRA). Workers exposed to noise and styrene had significantly poorer pure-tone thresholds in the high-frequency range (3 to 8 kHz) than the controls, noise-exposed workers and those listed in a Swedish age-specific database. Even though abnormalities were noted on DPOAE and CRA testing, the interrupted speech and speech recognition in noise tests were the more sensitive tests for styrene effects. Further research is needed on the underlying mechanisms to understand the effects of styrene and on audiological test batteries to detect changes in populations exposed to solvents.